Rebuiding midrangers on Thiels

Call Bill at Millersound.

Send them to Thiel. The Thiel drivers though appearing to be stock items are actually modified to Thiels specs. The midrange drivers for the 3.5's are a bit unusual in that they use paper surrounds. Though out of warranty, Thiel is rightly famous for their customer service, and typically pretty generous with regard to such repairs so long as the drivers weren't abused.

Thiel charges $300 each plus shipping to repair 3.5 mids. I would definitely check with Millersound before spending more than $600 to repair an $800 speaker system. If you are not familiar with Bill (Millersound) he is third generation in the speaker business and all of Bill's work is first class.

Rrog, without going into the details, let me just say that I've had my 3.5 midranges and some other Thiel drivers repaired by Thiel for a much more modest sum.
Though we haven't met, I've heard nothing but excellent reports about Bill of Millersound from people who deal with him often, I'm just outside of Philly.
If one were to choose Bill to do the work, considering the drivers custom mods done for Thiel, and that the Thiel cross-overs compensate for the drivers used, perhaps it would be a good idea to bring the good driver for comparison matching.

I had my 3.5 mid drivers rebuilt by Thiel around six years ago. I think I still have the invoice. I can tell you for a fact that it did not cost $300 per driver. That would make the rebuild cost more than what the speakers are worth. I want to say that it was around $75.00 per driver.

New replacement mid drivers are no longer available from Thiel for this model.

Unsound, Good idea providing you have a good driver.